…the central and most important part of an object, movement, or group, forming the basis for its activity and growth…
…the upper of the two grey nuclei of the corpus striatum in the cerebrum of the brain…
…each of a pair of small nuclei in the hypothalamus of the brain, above the optic chiasma, thought to be concerned with the regulation of physiological circadian rhythms…
…each of two protuberances on the inferior surface of the thalamus which relay auditory and visual impulses respectively to the cerebral cortex…
